Most origami boxes are modular pieces and to get a box this size, you would need really small modular units, which could turn out to be tedious to make. But this box is just perfect in size!
One thing that I would suggest is that, if you are giving this to someone, it would be better to glue the little pocket that is on the inside of the box. I also glued the join at the top of the box to prevent it from opening up!
Model Details:
Model: Heart Box
Creator: Robin Glynn
Difficulty Level: High Intermediate
Paper Ratio: A4 (297 mm * 210 mm)
Model Size: ~4 inches
Diagram: Origami Diagram
Tutorial: Youtube (Part 1 and Part 2)